Clinical Epidemiology of Extracranial Injuries in Severe Pediatric Traumatic Brain Injury in South America

BACKGROUND

Severe traumatic brain injury (TBI) is a leading cause of pediatric mortality, with a disproportionate burden on low- and middle-income countries. The impact of concomitant extracranial injury (ECI) on these patients remains unclear. This study is the first to characterize the epidemiology and clinical course of severe pediatric TBI with extracranial injuries in any South American country.

METHODS

We conducted a secondary analysis of baseline data collected prior to implementation of a clinical trial on TBI care in Argentina, Paraguay, and Chile from September 2019 to July 2020. Patients ≤18 years with CT evidence of TBI, and a Glasgow coma scale (GCS) score ≤8 were recruited. Patients were initially stratified by highest non-head abbreviated injury scale (AIS): isolated TBI (AIS=0), minor extracranial injury (MEI; AIS=1-2), and serious extracranial injury (SEI; AIS≥3). Patients were subsequently stratified by mechanism of injury. Intergroup differences were compared using ANOVA, two-tailed unpaired t-tests, and chi-square tests.

RESULTS

Among the 116 children included, 33 % (n = 38) had an isolated TBI, 34 % (n = 39) had MEI, and 34 % (n = 39) had SEI. Facial (n = 53), thoracic (n = 44), and abdominal (n = 31) injuries were the most common ECIs. At discharge, there were no significant differences in median GCS, GOS, or GOS-extended between groups. Patients with SEI had a longer hospital LOS than those with isolated TBI (median 28.0 (IQR 10.6-40.1) vs 11.9 (IQR 8.7-20.7) days, p = 0.013). The most common mechanisms of injury were road traffic injuries (RTIs) (n = 50, 43 %) and falls (n = 35, 30 %). Patients with RTI-associated TBIs were more likely to be older (median 11.0 (IQR 3.0-14.0) vs 2.0 (IQR 0.8-7.0) years, p<0.001) and more likely to have an ECI (86% vs 54 %, respectively; p = 0.003). ICU and Hospital LOS for RTI patients (median 10.5 (IQR 6.1-21.1) and 24.1 (IQR 11.5-40.4) days) were longer than those of fall patients (median 6.1 (IQR 2.6-8.9) and 13.7 (IQR 7.7-24.5) days).

CONCLUSIONS

Extracranial injuries are common in South American patients with severe TBI. Severe ECI is more frequently associated with RTIs and can result in a higher rate of surgical procedures and LOS. Further strategies are needed to characterize the prevention and treatment of severe pediatric TBI in the South American context.

Change in health-related quality of life and functional disability over time post-concussion in youth

PURPOSE

Concussions can have detrimental on children's cognitive, emotional, behavioral, and/or social functioning. We sought to examine changes in health-related quality of life (HRQOL) and functional disability from pre-injury to 1-week post-concussion, and to symptom resolution among youth ages 11-17 with a concussion.

METHODS

In this prospective, longitudinal cohort study, 83 concussed youth, ages 11-17, self-reported post-concussion symptoms daily as well as HRQOL and functional disability at baseline (pre-injury, retrospective), 1-week post-concussion, and symptom resolution. We modeled changes in overall and sub-scale HRQOL and functional disability scores over time from pre-injury to 1-week post-concussion and from 1-week post-concussion to symptom resolution using a piecewise linear mixed model, adjusting for potential covariables. Estimated fixed effects with a corresponding adjusted coefficient (beta), along with their 95% confidence intervals are presented.

RESULTS

Overall HRQOL worsened from pre-injury to 1-week post-injury (β = - 5.40, 95%CI - 9.22, - 1.58) but did not change from 1-week post-injury to symptom resolution. Physical HRQOL worsened from pre-injury to 1-week post-injury (β = - 9.90, 95%CI - 14.65, - 5.14) but improved from 1-week post-injury to symptom resolution (β = 1.64, 95%CI 0.50, 2.78), while psychosocial HRQOL showed no change over time. Functional disability worsened from pre-injury to 1-week post-injury (β = 8.36, 95%CI 5.93, 10.79) but with no change from 1-week post-injury to symptom resolution. Youth with symptom duration > 14 days reported worse HRQOL and functional disability than those who recovered in ≤ 14 days and greater daily post-concussion symptom scores were associated with worse HRQOL and functional disability.

CONCLUSION

Concussions have a negative impact on overall and physical HRQOL and functional disability in youth acutely post-injury. Ratings of HRQOL could be used to inform clinical treatment decisions to assist with the recovery process.

Age predicts likelihood for surgery for pediatric tbi: an analysis of 1745 hospitlizations from a Chinese Children's Hospital

PURPOSE

We tested the role of age and sex in surgery following pediatric TBI hospitalization.

METHODS

Records of 1745 children hospitalized at a pediatric neurotrauma center in China included age, sex, cause of injury, diagnosis of injury, days of hospitalization, in-house rehabilitation, Glasgow Coma Scale score, mortality, 6-month post-discharge Glasgow Outcome Scale score, and surgery intervention. The children were 0-13 years (M= 3.56 years; SD = 3.06), with 47.4% 0-2 years of age.

RESULTS

The mortality rate was 1.49%. Logistic regression on 1027 children with epidural hematoma, subdural hematoma, intracerebral hemorrhage, and intraventricular hemorrhage showed that controlling for other variables, the odds for younger children to receive surgery was statistically lower for epidural hematomas (OR = 0.75; 95% CI = 0.68-0.82), subdural hematomas (OR = 0.59; 95% CI = 0.47-0.74), and intraventricular hemorrhage (OR = 0.52; 95% CI = 0.28-0.98).

CONCLUSIONS

While severity of TBI and type of TBI were expected predictors for surgery, a younger age also predicted a significantly lower likelihood of surgery in our sample. Sex of the child was unrelated to surgical intervention.

History of pediatric TBI hospitalization and current child-parent relationship quality in China

BACKGROUND

Long-term child-parent relationship quality following hospitalization for pediatric traumatic brain injury (TBI) remains poorly understood.

OBJECTIVE

We tested whether current child-parent conflict and closeness were related to the children's history of TBI-related experiences and contemporary child/family characteristics.

METHODS

The sample included 202 Chinese children (Boys: 60.4%) with a history of hospitalization for TBI. On average, the children were 11.2 years old (SD = 1.59) and sustained TBI at 8.5 years old (SD = 1.6). TBI-related data were obtained from hospital medical records. Parents provided data on child-parent closeness, child-parent conflict, and parental efficacy 2-4 years (M = 2.7, SD = 0.7) after discharge.

RESULTS

Forty-nine children (24.3%) had mild TBI, 139 (68.8%) had moderate TBI, and 14 (6.9%) had severe TBI. Surgical intervention occurred among 128 (63.4%) of the 202 children. Contemporaneous child and family characteristics explained 19% of the variance, history of surgery, length of hospitalization, and recovery status explained another 7%, and the interaction between length of hospitalization and parental efficacy explained another 4% in child-parent conflict. Contemporaneous child and family characteristics explained 29% of the variance, and TBI-related variables explained another 2% in child-parent closeness.

CONCLUSION

Post-TBI child-parent relationship was more associated with child/family characteristics than with TBI variables. Practitioners and families should be aware of the long-term challenges to child-parent relationship following hospitalization for pediatric TBI.

Caregiver and Child Behavioral Health Service Utilization Following Pediatric Traumatic Brain Injury

Given sparse literature examining receipt of behavioral health service in children and caregivers following traumatic brain injury (TBI), we sought to identify predictors of unmet need. We performed an individual participant data meta-analysis using generalized linear mixed-effect models to examine predictors of behavioral health service use and unmet need. We included 572 children, ages 3 to 18, who were hospitalized overnight following complicated mild to severe TBI between 2002 and 2015. Caregivers completed ratings of depression and distress, child behavior problems, family functioning, and behavioral health service utilization. For children, unmet behavioral health service need was defined as an elevation on one or more child behavior problem scales without receipt of behavioral health services. For caregivers, unmet need was defined as an elevation on either a depression or distress scale without behavioral health service utilization. Among those with behavioral health needs, rates of unmet need were high for both children (77.8%) and caregivers (71.4%). Poorer family functioning was related to more unmet need in children (F(1, 497) = 6.57, p = 0.01; OR = 1.8) and caregivers (F(1, 492) = 17.54, p < 0.001; OR = 2.7). Children with unmarried caregivers also had more unmet behavioral health service need than those with married caregivers (F(1, 497) = 12.14, p < 0.001; OR = 2.2). In conclusion, unmet needs are common after pediatric TBI and relate to family factors. The findings underscore the importance of monitoring service needs following pediatric TBI and point to disparities in service use.

Progesterone treatment following traumatic brain injury in the 11-day-old rat attenuates cognitive deficits and neuronal hyperexcitability in adolescence

Traumatic brain injury (TBI) in children younger than 4 years old results in cognitive and psychosocial deficits in adolescence and adulthood. At 4 weeks following closed head injury on postnatal day 11, male and female rats exhibited impairment in novel object recognition memory (NOR) along with an increase in open arm time in the elevated plus maze (EPM), suggestive of risk-taking behaviors. This was accompanied by an increase in intrinsic excitability and frequency of spontaneous excitatory post-synaptic currents (EPSCs), and a decrease in the frequency of spontaneous inhibitory post-synaptic currents in layer 2/3 neurons within the medial prefrontal cortex (PFC), a region that is implicated in both object recognition and risk-taking behaviors. Treatment with progesterone for the first week after brain injury improved NOR memory at the 4-week time point in both sham and brain-injured rats and additionally attenuated the injury-induced increase in the excitability of neurons and the frequency of spontaneous EPSCs. The effect of progesterone on cellular excitability changes after injury may be related to its ability to decrease the mRNA expression of the β3 subunit of the voltage-gated sodium channel and increase the expression of the neuronal excitatory amino acid transporter 3 in the medial PFC in sham- and brain-injured animals and also increase glutamic acid decarboxylase mRNA expression in sham- but not brain-injured animals. Progesterone treatment did not affect injury-induced changes in the EPM test. These results demonstrate that administration of progesterone immediately after TBI in 11-day-old rats reduces cognitive deficits in adolescence, which may be mediated by progesterone-mediated regulation of excitatory signaling mechanisms within the medial PFC.

Early Decompressive Craniectomy as Management for Severe Traumatic Brain Injury in the Pediatric Population: A Comprehensive Literature Review

BACKGROUND

Severe traumatic brain injuries (TBIs) are a principal cause of neurologic dysfunction and death in the pediatric population. After medical management, the second-tier treatment is decompressive craniectomy in cases of intractable intracranial pressure (ICP) elevation. This literature review offers evidence of early (within 24 hours) and ultraearly (6-12 hours) decompressive craniectomy as an effective form of management for severe TBI in the pediatric population.

METHODS

We conducted a literature review of articles published from 1996 to 2019 to elucidate neurologic outcomes after early decompressive craniectomy in pediatric patients who suffered a severe TBI. Time to decompressive craniectomy and neurologic outcomes were recorded and reported descriptively. Qualitative data describe clinically important correlations between pre- and postoperative ICP levels and improved postoperative neurologic outcomes.

RESULTS

Seventy-eight patients were included in this study. The median age of patients at diagnosis was 10 years of age (range, 1 months to 19 years). Median admission Glasgow Coma Scale score was 5 (range, 3-8). Time to decompressive craniectomy ranged from 1 to 24 hours. Median peak preoperative ICP was 40 (range, 3-90; n = 49). Median postoperative ICP was 20 (range, 0-80; n = 33). Median Glasgow Outcome Scale (GOS) score at discharge was 2 (range, 1-5; n = 11). Median GOS score at 3- and 6-month follow-up was 3 (range, 1-5; n = 11). Median GOS score at 7- to 23-month follow-up was 4 (range, 1-5; n = 29). Median GOS score at 24- to 83-month follow-up was 4 (range, 1-5; n = 31). Median modified Rankin Scale score at discharge was 3 (range, 2-4; n = 6). Median modified Rankin Scale score at 6- to 48-month follow-up was 2 (range, 0-3; n = 6). Median Rancho Los Amigos Scale (RLAS) score at discharge was 6 (range, 4-8; n = 5). Median RLAS score at 6-month follow-up was 10 (range, 8-10; n = 5).

CONCLUSIONS

Early (within 24 hours), with consideration of ultraearly (within 6-12 hours), decompressive craniectomy for severe TBI should be offered to pediatric patients in settings with refractory ICP elevation. Reduction of ICP allows for prompt disruption of pathophysiologic cascades and improved neurologic outcomes.

Neuroimmune responses in the developing brain following traumatic brain injury

Traumatic brain injury (TBI) is one of the leading causes of both acute and long-term morbidity in the pediatric population, leading to a substantial, long-term socioeconomic burden. Despite the increase in the amount of pre-clinical and clinical research, treatment options for TBI rely heavily on supportive care with very limited targeted interventions that improve the acute and chronic sequelae of TBI. Other than injury prevention, not much can be done to limit the primary injury, which consists of tissue damage and cellular destruction. Secondary injury is the result of the ongoing complex inflammatory pathways that further exacerbate tissue damage, resulting in the devastating chronic outcomes of TBI. On the other hand, some level of inflammation is essential for neuronal regeneration and tissue repair. In this review article we discuss the various stages of the neuroimmune response in the immature, pediatric brain in the context of normal maturation and development of the immune system. The developing brain has unique features that distinguish it from the adult brain, and the immune system plays an integral role in CNS development. Those features could potentially make the developing brain more susceptible to worse outcomes, both acutely and in the long-term. The neuroinflammatory reaction which is triggered by TBI can be described as a highly intricate interaction between the cells of the innate and the adaptive immune systems. The innate immune system is triggered by non-specific danger signals that are released from damaged cells and tissues, which in turn leads to neutrophil infiltration, activation of microglia and astrocytes, complement release, as well as histamine release by mast cells. The adaptive immune response is subsequently activated leading to the more chronic effects of neuroinflammation. We will also discuss current attempts at modulating the TBI-induced neuroinflammatory response. A better understanding of the role of the immune system in normal brain development and how immune function changes with age is crucial for designing therapies to appropriately target the immune responses following TBI in order to enhance repair and plasticity.

Bridging the gap: Mechanisms of plasticity and repair after pediatric TBI

Traumatic brain injury is the leading cause of death and disability in the United States, and may be associated with long lasting impairments into adulthood. The multitude of ongoing neurobiological processes that occur during brain maturation confer both considerable vulnerability to TBI but may also provide adaptability and potential for recovery. This review will examine and synthesize our current understanding of developmental neurobiology in the context of pediatric TBI. Delineating this biology will facilitate more targeted initial care, mechanism-based therapeutic interventions and better long-term prognostication and follow-up.

Depletion of microglia immediately following traumatic brain injury in the pediatric rat: Implications for cellular and behavioral pathology

The inflammatory response is a significant component of the pathophysiology of pediatric traumatic brain injury. High levels of inflammatory mediators have been found in the cerebrospinal fluid of brain-injured children which have been linked to poor prognosis. Targeting aspects of the inflammatory response in the hopes of finding a viable post-injury therapeutic option has gained attention. Microglia are largely responsible for perpetuating the injury-induced inflammatory response but in the developing brain they play beneficial roles in both normal and disease states. Following closed head injury in the neonate rat, depletion of microglia with intracerebral injections of liposomes containing clodronate was associated with an increase in neurodegeneration in the early post-injury period (3 days) relative to those injected with empty liposomes suggestive of a decrease in clearance of dying cells. In sham-injured animals, microglia repopulated the clodrosome-mediated depleted brain regions over a period of 2-4 weeks and exhibited morphology typical of a resting phenotype. In brain-injured animals, the repopulated microglia in clodrosome-injected animals exhibited rod-like and amoeboid morphologies. However, fluoro-Jade B reactivity in these brain regions was more extensive than in empty liposome-injected animals suggesting that the active microglia may be unable to clear dying neurons. This was accompanied by an induction of hyperexcitability in the local cortical circuitry. Depletion of microglia within the white matter tracts and the thalamus did not affect the extent of injury-induced traumatic axonal injury. Increased neurodegeneration in the dorsal subiculum was not accompanied by any changes to injury-induced deficits in spatial learning and memory. These data suggest that activation of microglia may be important for removal of dying neurons in the traumatically-injured immature brain.

Differential effects of minocycline on microglial activation and neurodegeneration following closed head injury in the neonate rat

The role of microglia in the pathophysiology of injury to the developing brain has been extensively studied. In children under the age of 4 who have sustained a traumatic brain injury (TBI), markers of microglial/macrophage activation were increased in the cerebrospinal fluid and were associated with worse neurologic outcome. Minocycline is an antibiotic that decreases microglial/macrophage activation following hypoxic-ischemia in neonatal rodents and TBI in adult rodents thereby reducing neurodegeneration and behavioral deficits. In study 1, 11-day-old rats received an impact to the intact skull and were treated for 3days with minocycline. Immediately following termination of minocycline administration, microglial reactivity was reduced in the cortex and hippocampus (p<0.001) and was accompanied by an increase in the number of fluoro-Jade B profiles (p<0.001) suggestive of a reduced clearance of degenerating cells; however, this effect was not sustained at 7days post-injury. Although microglial reactivity was reduced in the white matter tracts (p<0.001), minocycline treatment did not reduce axonal injury or degeneration. In the thalamus, minocycline treatment did not affect microglial reactivity, axonal injury and degeneration, and neurodegeneration. Injury-induced spatial learning and memory deficits were also not affected by minocycline. In study 2, to test whether extended dosing of minocycline may be necessary to reduce the ongoing pathologic alterations, a separate group of animals received minocycline for 9days. Immediately following termination of treatment, microglial reactivity and neurodegeneration in all regions examined were exacerbated in minocycline-treated brain-injured animals compared to brain-injured animals that received vehicle (p<0.001), an effect that was only sustained in the cortex and hippocampus up to 15days post-injury (p<0.001). Whereas injury-induced spatial learning deficits remained unaffected by minocycline treatment, memory deficits appeared to be significantly worse (p<0.05). Sex had minimal effects on either injury-induced alterations or the efficacy of minocycline treatment. Collectively, these data demonstrate the differential effects of minocycline in the immature brain following impact trauma and suggest that minocycline may not be an effective therapeutic strategy for TBI in the immature brain.